Use of aluminum in perforating and stimulating a subterranean formation and other engineering applications

Abstract

A chemical reaction between molten aluminum and an oxygen carrier such as water to do useful work is disclosed, and in particular two chemical methods to obtain aluminum in its molten state. One is to detonate a HE / Al mixture with surplus Al in stoichiometry, and the other is to use an oxidizer / Al mixture with surplus Al in stoichiometry. Additionally, there is a physical method of shocking and heating Al using high temperature reaction products. The produced Al in its liquid form is forced to react with an oxygen carrying liquid (e.g. water), giving off heat and releasing hydrogen gas or other gaseous material. A water solution of some oxygen-rich chemicals (e.g. ammonium nitrate) can be advantageously used in place of water. A shaped charge is also disclosed having a liner that contains aluminum, propelled by a high explosive such as RDX or its mixture with aluminum powder. Some aluminum in its molten state is projected into the perforation and forced to react with water that also enters the perforation, creating another explosion, fracturing the crushed zone of the perforation and initializing cracks. Another shaped charge is shown having a liner of energetic material such as a mixture of aluminum powder and a metal oxide. Upon detonation, the collapsed liner carries kinetic and thermal energy. Also shown are methods to build and to detonate or fire explosive devices in an oxygen carrying liquid (e.g. water) to perforate and stimulate a hydrocarbon-bearing formation.

Description

FIELD OF THE INVENTION[0001]The present invention relates to the use of aluminum in general, and in particular to the chemical reaction between molten aluminum and an oxygen carrier such as water to do useful work in engineering.BACKGROUND OF THE INVENTION[0002]Aluminum (“Al”), the most abundant metallic element in the earth's crust, is a light weight, silver metal. Its atomic weight is 26.9815, and its specific gravity is 2.7. The element melts at 660° C. and boils at 2467° C. In today's explosives and ordnance industries, aluminum is used in its powder form in explosives and propellants due to the high heat value it generates when it reacts with oxygen. The heat released by oxidizing 1 gram of aluminum into aluminum oxide is 30.95 KJ, compared to the detonation heat of some most often used high explosives, for example, the tested detonation heat of RDX (Hexogen, Cyclotrimethylenetrinitramine) is 6.32 KJ / gram, and that of HMX (Octogen, Cyclotetramethylenetetranitramine) is 6.19 KJ / ...

AI Technical Summary

Benefits of technology

[0029]Consequently, a first objective of the present invention is to exploit the large amount of energy generated by the oxidation of aluminum from an aluminum-water reaction (or the reaction of aluminum with other oxidizers such as a metal oxide) for engineering applications, an in particular to provide a method to rapidly, economically produce molten aluminum in its free form in large quantities. The molten aluminum should preferably be produced from an explosive detonation process or from a rapid combustion of a fuel-oxidizer mixture so that a “dual-explosion” can be created. The first explosion of such a “dual-explosion” is the detonation of the high explosives or the combustion of the fuel-oxidizer mixture, and the second explosion is the aluminum-water reaction. When such a “dual-explosion” is created in a medium such as water, steel casing or tubing, hydrocarbon bearing formation, rock stratum or concrete etc., the mechanical effects resulting from the first explosion will be greatly enhanced or improved by the second explosion. The mechanical effects in the medium can be the mechanical effects for which an explosive device is designed to achieve, which may include, but is not limited to, one or a combination of the following effects: pressure wave generation and propagation, pressurization and displacement of medium, target penetration and fracturing, crack initialization and propagation, medium disintegration, fragmentation and fragment movement, etc.

[0030]A second objective of the present invention is to increase the reactivity between molten aluminum and water so that the minimum temperature required for aluminum for a complete reaction to occur can be lowered and the energy output from the reaction can be increased.

[0036]An eighth objective of the invention is to provide a method and device to be used in drilled holes filled with water or water solution of some oxygen-rich reagents for rock blasting, pre-splitting, concrete structure blasting, cutting and demolition that can create two consecutive explosions and enhanced mechanical effects.

[0038]A tenth objective of the invention is to provide a method to make a torpedo suitable for defense applications. Unlike prior art torpedoes, it creates two consecutive explosions with much more energy output and enhanced mechanical effects when launched and set off underwater.

Problems solved by technology

The molten aluminum is then forced to react with water to create an explosion locally within the perforation, fracturing the crushed zone of the perforation and initializing a multitude of cracks.

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